In accordance with a rapid spread of information relevant apparatuses and communication apparatuses such as a personal computer, a video camera and a portable telephone in recent years, the development of a battery to be utilized as a power source thereof has been emphasized. The development of a high-output and high-capacity battery for an electric automobile or a hybrid automobile has been advanced also in the automobile industry. A lithium ion battery has been presently noticed from the viewpoint of a high energy density among various kinds of batteries.
A sulfide solid electrolyte material has been known as an electrolyte material used in a lithium ion battery. For example, Patent Literature 1 discloses a method for producing a sulfide solid electrolyte material, the method comprising drying a precursor aqueous solution containing LiI and LiOH, and after that, conducting a sulfidization treatment, a de-sulfide-hydrogenating treatment, and a synthesizing treatment. Also, Patent Literature 2 discloses a method for producing a sulfide solid electrolyte material, the method comprising preparing a raw material mixture containing LiHS and LiX (X is F, Cl, Br, or I) from a single Li source, and after that, conducting a de-sulfide-hydrogenating treatment and a synthesizing treatment.